• Archives of Pharmacal Research
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• 제13권3호
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• pp.233-239
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• 1990

The efect of acute renal failure (ARF) on the pharmacokinetics o sulfobromophthalein (BSP) was investigated in order to elucidate if renal failure modifies the hepatic metabolism of drugs. ARF was induced by intravenous (iv) injection of uranyl nitrate (UN) to rats (5 mg/kg) five days before the experiment. Area under the plasma concentration-time curve (AUC)of BSP after portal vein (pv) injection increased by 2-fold and total body clearance ($CL_1$) decreased one half (p <0.01) in UN-induced ARF (UN-ARF) rate compared to the control rats. But the plasma disappearance of BSP after iv injection did not differ significantly between control and UN-ARF rats. Since BSP is excreted via the liver, $CL_1$ represented the approximate hepatic clearance of BSP. Therefore, the decrease in $CL_1$ represented the approximate hepatic clearance of BSP. Therefore, the decrease in $CL_1$ represents a decrease in hepatic intrinsic clearance ($CL_{int}$) for BSP since plasma free fraction ($f_p$) of BSP was not affected by UN-ARF. The content of hepatic cytoplasmic Y-protein, which catalyzes BSP-glutathione conjugation and limits the trasfer of BSP from blood to bile, increased significantly (p < 0.01), however its binding activity (BA) for BSP was decreased significantly (p <0.01) by UN-ARF. The decrease in $CL_{int}$might have some correlation with the changed characteristics of hepatic Y-protein, specifically its decreased BA for BSP.

• Geomechanics and Engineering
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• 제18권6호
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• pp.595-603
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• 2019

A modified model combining Kriging and Monte Carlo method (MC) is proposed for probabilistic estimation of tunnel face stability in this paper. In the model, a novel uniform design is adopted to train the Kriging, instead of the existing active learning function. It has advantage of avoiding addition of new training points iteratively, and greatly saves the computational time in model training. The kinematic approach of limit analysis is employed to define the deterministic computational model of face failure, in which the Hoek-Brown failure criterion is introduced to account for the nonlinear behaviors of rock mass. The trained Kriging is used as a surrogate model to perform MC with dramatic reduction of calls to actual limit state function. The parameters in Hoek-Brown failure criterion are considered as random variables in the analysis. The failure probability is estimated by direct MC to test the accuracy and efficiency of the proposed probabilistic model. The influences of uncertainty level, correlation relationship and distribution type of random variables are further discussed using the proposed approach. In summary, the probabilistic model is an accurate and economical alternative to perform probabilistic stability analysis of tunnel face excavated in spatially random Hoek- Brown media.

• Geomechanics and Engineering
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• 제17권1호
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• pp.109-118
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• 2019

The movement of soil along a slope during rainfall can cause serious economic damage and can jeopardize human life. Accordingly, predicting slope stability during rainfall is a major issue in geotechnical engineering. Due to rainwater penetrating the soil, the negative pore water pressure will decrease, in turn causing a loss of shear strength in the soil and ultimately slope failure. More seriously, many constructions such as houses and transmission towers built in/on slopes are at risk when the slopes fail. In this study, the numerical simulation using 2D finite difference program, which can solve a fully coupled hydromechanical problems, was used to evaluate the effects of soil properties, rainfall conditions, and the location of a foundation on the slope instability and slope failure mechanisms during rainfall. A slope with a transmission tower located in Namyangju, South Korea was analyzed in this study. The results showed that the correlation between permeability and rainfall intensity had an important role in changing the pore water pressure via controlling the infiltrated rainwater. The foundation of the transmission tower was stable during rainfall because the slope failure was estimated to occur at the toe of the slope, and did not go through the foundation.

• 한국동물위생학회지
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• 제46권3호
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• pp.181-192
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• 2023

Cystatin C, a low-molecular-weight protein synthesized by cells, is being explored as a valuable biomarker for assessing renal function in veterinary medicine. Although the relationship between cystatin C and heart disease remains unclear, some studies suggest a possible association. This retrospective case-control study aimed to investigate the role of cystatin C as a biomarker for heart disease and its correlation with diuretic use in veterinary clinical practice. A total of 39 dogs were included in this study, comprising 9 control dogs without a predisposition to heart disease and 30 dogs in the study group diagnosed with heart disease. Among the 30 dogs with heart disease, 18 exhibited symptoms indicative of heart failure. Results showed significantly higher cystatin C levels in the heart disease group compared to the control group (P<0.05). However, no significant differences were observed among different stages of heart disease severity in the control group. Furthermore, cystatin-C showed statistically positive correlations with BUN (r=0.478, P<0.01), creatinine (r=0.506, P<0.01), and furosemide (r=0.338, P<0.05). Diuretics are essential for managing congestive heart failure, and the observed associations between cystatin C and furosemide suggest potential impacts of diuretic use on renal function in dogs with heart failure. Monitoring renal function markers, such as cystatin C, can aid in predicting and managing potential renal complications, ultimately improving the overall health and quality of life of dogs with heart disease.

• Corrosion Science and Technology
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• 제22권3호
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• pp.153-163
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• 2023

Two types of accelerated tests, Water Drop Test (WDT) and Temperature-Humidity-Bias Test (THBT), can be used to evaluate the susceptibility to electrochemical migration (ECM). In the WDT, liquid water is directly applied to a specimen, typically a patterned conductor like a printed circuit board. Time to failure in the WDT typically ranges from several seconds to several minutes. On the other hand, the THBT is conducted under elevated temperature and humidity conditions, allowing for assessment of design and life cycle factors on ECM. THBT is widely recognized as a more suitable method for reliability testing than WDT. In both test methods, localized corrosion can be observed on the anode. Composition of dendrites formed during the WDT is similar to that formed during THBT. However, there is a lack of correlation between the time to failure obtained from WDT and that obtained from THBT. In this study, we investigated the relationship between electrochemical parameters and time to failure obtained from both WDT and THBT. Differences in time to failure can be attributed to actual anode potential obtained in the two tests.

• Computers and Concrete
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• 제34권1호
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• pp.15-31
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• 2024

This study explores the failure mechanisms of 'I' shaped non-persistent cracks under uniaxial loads through a combination of experimental tests and numerical simulations. Concrete specimens measuring 200 mm×200 mm×50 mm were manufactured, featuring 'I' shaped non-persistent joints. The number of these joints varied from one to three, with angles set at 0, 30, 60, and 90 degrees. Twelve configurations, differing in the placement of pre-existing joints, were considered, where larger joints measured 80 mm in length and smaller cracks persisted for 20 mm with a 1 mm crack opening. Numerical models were developed for the 12 specimens, and loading in Y-axis direction was 0.05 mm/min, considering a concrete tensile strength of 5 MPa. Results reveal that crack starting was primarily influenced by the slope of joint that lacks persistence in relation to the loading direction and the number of joints. The compressive strength of the samples exhibited variations based on joint layout and failure mode. The study reveals a correlation between the failure behavior of joints and the number of induced tensile fracture, which increased with higher joint angles. Specimen strength increased with decreasing joint angles and numbers. The strength and failure processes exhibited similarities in both laboratory testing and numerical modeling methods.

• 대한핵의학회지
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• 제16권1호
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• pp.7-14
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• 1982

In an attempt to evaluate the various serum hormonal changes in terminal renal failure, the fasting $T_4,\;T_3,\;rT_3$, gastrin, secretin prolactin, and aldosterone were measured by radioimmunoassay in 12 patients with chronic renal failure, who were admitted to Chosun University Hospital from January to June, 1981. From the analysis the following results were obtained. 1. Mean values of serum hormonal concentration in 10 normal control were as follows: $T_4,\;12.93{\pm}2.00ug/ml$; $T_3,\;113.0{\pm}28.7ng/ml$; $rT_3,\;0.11{\pm}0.10ng/ml$; gastrin, $100.0{\pm}47.1pg/ml$; secretin, $32.46{\pm}11.45pg/ml$; prolactin, $11.0{\pm}3.6ng/ml$; aldosterone, $137.0{\pm}58.5pg/ml$, 2. Mean values of serum hormonal concentration in 12 chronic renal failure were as follows: $T_4,\;7.34{\pm}2.43ug/ml$; $T_3,\;71.0{\pm}19.1ng/ml$; reverse $T_3,\;0.38{\pm}0.19ng/ml$; gastrin, $162.5{\pm}40.2pg/ml$; secretin, $107.50{\pm}20.48pg/ml$; prolactin, $34.0{\pm}17.2ng/ml$; Aldosterone, $86.5{\pm}19.8pg/ml$. 3. In chronic renal failure group, serum T 4, T 3 and adosterone level were significantly lower than those of the control group, but serum $rT_3$, gastrin, secretin and prolactin were significantly higher than those of the control group. 4. In the view of the correlation between serum hormonal concentions and serum creatinine levels in patients with chronic renal failure, $rT_3$, gastrin, secretin and prolactin showed increasing tendency(positive correlations), whereas $T_4,\;T_3$ and aldosterone showed decreasing tendency (negative correlations) with increment of serum cteatinine levels. And so, we observed the negative correlation between $T_3\;and\;rT_3$.

• Journal of Chest Surgery
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• 제26권3호
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• pp.170-179
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• 1993

Three hundred consecutive adult patients having cardioaortic surgery under the cardiopulmonary bypass for a variety of cardioaortic lesions were evaluated retrospectively for postoperative hyperbilirubinemia[above 5mg/100ml].We found twenty eight patients with postoperative hyperbilirubinemia and divided them into two groups according to the postoperative day of peak s-bilirubin .Group A was the patients with a peak s-bilirubin level within three days ,and group B above three days postoperatively.Group B was divided into group S[survive] and group D[death] . We had compaired the survival & death group and observed the correlation between the decreasing tendency of postoperative s-bilirubin & the nutrition per os in group B. The incidence of postoperative hyperbilirubinemia,as defined by a s-bilirubin concentration of 5.0mg/100ml or greater,was 9.3%.The mortality rates of group A & B were 0.0% and 35.7% respectively.Important contributing factors between group A & B were the age,duration of ICU,Max.DOAB[maximum dose of catecholamine used],amount of blood transfused during or shortly after surgery and preoperative pulmonary hypertension[main pulmonary artery pressure > 30mmHg] and backward heart failure. The risking factors of group D compared to group S were as follows the age,preoperative & postoperative SGOT[serum glutamic-oxaloacetic trasaminase],postoperative total & indirect bilirubin,cardiopulmonary bypass time,duration of ICU & mechanical ventilation ,Max.DOAB,preoperative pulmonary hypertension and backward heart failure.The six patients in group B showed good correlation between the decreasing point of s-bilirubin and the starting day of oral or tube feeding.

• 한국지진공학회논문집
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• 제25권5호
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• pp.191-199
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• 2021

In seismic design, hollow section concrete columns offer advantages by reducing the weight and seismic mass compared to concrete section RC bridge columns. However, the flexure-shear behavior and spirals strain of hollow section concrete columns are not well-understood. Octagonal RC bridge columns of a small-scale model were tested under cyclic lateral load with constant axial load. The volumetric ratio of the transverse spiral hoop of all specimens is 0.00206. The test results showed that the structural performance of the hollow specimen, such as the initial crack pattern, initial stiffness, and diagonal crack pattern, was comparable to that of the solid specimen. However, the lateral strength and ultimate displacement of the hollow specimen noticeably decreased after the drift ratio of 3%. The columns showed flexure-shear failure at the final stage. Analytical and experimental investigations are presented in this study to understand a correlation confinement steel ratio with neutral axis and a correlation between the strain of spirals and the shear resistance capacity of steel in hollow and solid section concrete columns. Furthermore, shear strength components (V_c, V_s·, V_p) and concrete stress were investigated.

• 한국지반신소재학회논문집
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• 제21권1호
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• pp.33-48
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• 2022

This paper presents illustrative examples of the application of advanced digital image correlation (DIC) technology in the geotechnical laboratory tests, such as shallow footing test, trapdoor test, retaining wall test, and wide width tensile test on geogrid. The theoretical background of the DIC technique is first introduced together with fundamental equations. Relevant reduced-scale model tests were then performed using standard sand while applying the DIC technique to capture the movement of target materials during tests. A number of different approaches were tried to obtain optimized images that allow efficient tracking of material speckles based on the DIC technique. In order to increase the trackability of soil particles, a mix of dyed and regular sand was used during the model tests while specially devised painted speckles were applied to the geogrid. A series of images taken during tests were automatically processed and analyzed using software named VIC-2D that automatically generates displacements and strains. The soil deformation field and associated failure patterns obtained from the DIC technique for each test were found to compare fairly well with the theoretical ones. Also shown is that the DIC technique can also general strains appropriate to the wide width tensile test on geogrid, It is demonstrated in this study that the advanced DIC technique can be effectively used in monitoring the deformation and strain field during a reduced-scale geotechnical model laboratory test.